Below is a good way to block it at the outlook level. You could just set a policy to limit the size of messages that are allowed to be sent to any user.

There are a number of file extensions that Outlook blocks by default. In fact, there are too many to list here, but they primarily consist of extensions used by executable files and system files. You can see the full list here if you're interested.

You can customize Outlook's blocking rules by editing the system registry.

Important: If you make a mistake when editing the registry, you can seriously impair Windows and/or your applications. Make sure you always perform a full system backup before playing with the registry.

1. Open the Registry Editor and navigate to HKEY_CURRENT_USER\Software\Microsoft\Office\11.0\Outlook\Security.
2. Select New -> String Value from the Registry Editor's Edit menu.
3. Create a new string value named Level1Add (this is case sensitive).
4. Then assign the string a value corresponding to the file extension that you want to block. For example, if you wanted to block Word documents, you would assign the value .DOC. (You can enter multiple extensions by separating them with a semicolon.)

You originally said the outlook client was a possibility, noting that the macro will automatically run on receipt of an email deleting attachments is it the case that this would not be appropriate for your needs?

Chris

0

mn10191bAuthor Commented: 2008-02-08

I would like to create the rule via Outlook client and the rule ends up on the server. So the rule fires even when outlook is not running. The mailbox in question is for a software application to track email volume. So nobody will run Outlook to check it if it runs normal.

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